Fix email validator in PHP

Notice: Array to string conversion in Egulias\EmailValidator\EmailValidator->isValid() (line 79 of vendor/egulias/email-validator/src/Egulias/EmailValidator/EmailValidator.php).
Egulias\EmailValidator\EmailValidator->isValid(Array)
mailchimp_validate_email(Array, Object, Array)
call_user_func_array('mailchimp_validate_email', Array)
Drupal\Core\Form\FormValidator->doValidateForm(Array, Object)
Drupal\Core\Form\FormValidator->doValidateForm(Array, Object)
Drupal\Core\Form\FormValidator->doValidateForm(Array, Object, 'mailchimp_signup_subscribe_block_my_form_form')
Drupal\Core\Form\FormValidator->validateForm('mailchimp_signup_subscribe_block_my_form_form', Array, Object)
Drupal\Core\Form\FormBuilder->processForm('mailchimp_signup_subscribe_block_my_form_form', Array, Object)
Drupal\Core\Form\FormBuilder->buildForm(Object, Object)
Drupal\Core\Form\FormBuilder->getForm(Object)
Drupal\mailchimp_signup\Plugin\Block\MailchimpSignupSubscribeBlock->build()
Drupal\block\BlockViewBuilder::preRender(Array)
call_user_func('Drupal\block\BlockViewBuilder::preRender', Array)
Drupal\Core\Render\Renderer->doRender(Array)
Drupal\Core\Render\Renderer->doRender(Array, )
Drupal\Core\Render\Renderer->render(Array)
Drupal\Core\Template\TwigExtension->escapeFilter(Object, Array, 'html', NULL, 1)
__TwigTemplate_d65800e29d5d31d5c0ef2e4bcffca04d695ff5b5116769a25426b0676b3fa2e9->doDisplay(Array, Array)
Twig_Template->displayWithErrorHandling(Array, Array)
Twig_Template->display(Array)
Twig_Template->render(Array)
twig_render_template('core/themes/bartik/templates/page.html.twig', Array)
Drupal\Core\Theme\ThemeManager->render('page', Array)
Drupal\Core\Render\Renderer->doRender(Array, )
Drupal\Core\Render\Renderer->render(Array)
Drupal\Core\Template\TwigExtension->escapeFilter(Object, Array, 'html', NULL, 1)
__TwigTemplate_79484e64d2dc79deeed0209e5cc378aecd3496624fcdc700477bd1826df95749->doDisplay(Array, Array)
Twig_Template->displayWithErrorHandling(Array, Array)
Twig_Template->display(Array)
Twig_Template->render(Array)
twig_render_template('core/themes/classy/templates/layout/html.html.twig', Array)
Drupal\Core\Theme\ThemeManager->render('html', Array)
Drupal\Core\Render\Renderer->doRender(Array, )
Drupal\Core\Render\Renderer->render(Array)
Drupal\Core\Render\MainContent\HtmlRenderer->Drupal\Core\Render\MainContent\{closure}()
Drupal\Core\Render\Renderer->executeInRenderContext(Object, Object)
Drupal\Core\Render\MainContent\HtmlRenderer->renderResponse(Array, Object, Object)
Drupal\Core\EventSubscriber\MainContentViewSubscriber->onViewRenderArray(Object, 'kernel.view', Object)
Drupal\Component\EventDispatcher\ContainerAwareEventDispatcher->dispatch('kernel.view', Object)
Symfony\Component\HttpKernel\HttpKernel->handleRaw(Object, 1)
Symfony\Component\HttpKernel\HttpKernel->handle(Object, 1, 1)
Drupal\Core\StackMiddleware\Session->handle(Object, 1, 1)
Drupal\Core\StackMiddleware\KernelPreHandle->handle(Object, 1, 1)
Drupal\page_cache\StackMiddleware\PageCache->pass(Object, 1, 1)
Drupal\page_cache\StackMiddleware\PageCache->handle(Object, 1, 1)
Drupal\Core\StackMiddleware\ReverseProxyMiddleware->handle(Object, 1, 1)
Drupal\Core\StackMiddleware\NegotiationMiddleware->handle(Object, 1, 1)
Stack\StackedHttpKernel->handle(Object, 1, 1)
Drupal\Core\DrupalKernel->handle(Object)